I do the same as Lufa. I used to just go by the number of days, about 10 to 14. Now I look for a steady reading for at least a few days. The trick is to be just as clean as you are on brew day. I started bleaching and cleaning everything before I take my readings. Better safe than sorry.
Prost!

I'm not a slacker in society. I'm an over achieving homeless person.
Drunk posting should be reserved for The RAT PAD!!